1. Field of the Invention
The present invention relates to a stimuli-responsive composition which contains a polymer, a solvent and a substance having a predetermined function, and which is usable for various functional materials. More particularly, the present invention relates to a composition which is an aqueous dispersion, and also relates to an image-forming material which is favorably usable for printers and displays, and a device, an image-forming method and an image-forming apparatus using it.
The present invention also relates to an ABC type triblock polymer compound which is an ABC type block polymer compound, and which comprises, as respective blocks, an A block which is solvent-phobic (hereinafter called solvophobic), a B block which changes in nature from solvent-philic (hereinafter called solvophilic) to solvophobic or from solvophobic to solvophilic in response to stimuli, and a C block which is solvophilic. More preferably, the invention relates to an ABC type triblock polymer compound in which each of the blocks changes in nature from solvophobic to solvophilic or from solvophilic to solvophobic in response to stimuli, and this change occurs sequentially, first in the A block, then in the B block, and finally in the C block.
2. Description of the Related Art
Among dispersion materials containing particulate solids, coloring materials, such as ink and toner, which contain colorants as particulate solids, have been widely known as functional materials. In recent years, digital printing techniques have advanced with marked momentum. Typical examples of the digital printing techniques are electrophotography and ink-jet technology. Their presence has drawn increased attention as image-forming techniques in the office and at home.
Of them, the ink-jet technology has great features, compactness and reduced power consumption, as a direct method of image-forming. In this technology, a high image quality has been achieved promptly because of a fine nozzle and so on. An example of the ink-jet technology is a so-called bubble jet (a registered trademark) method by which ink supplied from an ink tank is heated with a heater in the nozzle to cause film boiling, and the ink is ejected by the force of the film boiling to form an image on a recording medium. Another example is a method which involves vibrating a piezo element to eject ink from the nozzle. In these methods, further improvements are desired to counter bleeding or feathering. To realize these improvements, the use of pigment dispersion ink is under study (for example, U.S. Pat. No. 5,085,698), but a further improvement is desired.